Fluoridation of water may prevent some cavities, but it should not be done by municipalities. There are numerous fluoride products people can buy on their own, like rinses or topical applications that could be administered by a dentist. People should be able to decide for themselves if fluoride is something they want. In addition, certain people may be allergic or have negative reactions.
No, water fluoridation is not bad, because it is an easy way to help a lot of people be healthier. Putting fluoride in water has helped countless people who cannot afford proper dental care. The people in the United States have better dental hygiene than anyone else in the world. These efforts are to be commended. Fluoride is part of this.